Alpha-synuclein has a central role in the pathogenesis of Parkinson's disease, yet how it triggers dopaminergic neuron toxicity is poorly understood. Recent gene microarray studies in transgenic alpha-synuclein mice have shown that over-expression of alpha-synuclein results in decreased expression of a class of genes encoding the 14-3-3 proteins. Because the 14-3-3s regulate key signaling cascades, including apoptosis, the decrease in 14-3-3s may be an important step in alpha-synuclein-induced toxicity. The candidate has obtained preliminary data supporting the neuroprotective potential of the 14-3-3 proteins, particularly the theta isofom. Proposed experiments will determine the extent to which 14-3-3 isoforms can mitigate alpha-synuclein toxicity in both in vitro and in vivo models of Parkinson's disease and whether they can reduce apoptotic factor activity in these models. Potential mechanisms of how alpha-synuclein causes decreased 14-3-3 expression will be examined. Studies to evaluate the role of phosphorylation in the interaction between 14-3-3s and alpha-synuclein will also be performed. Results from these studies will look to validate the 14-3-3 proteins as potential targets for therapy in Parkinson's disease and related disorders. The research portion of the proposed career development program will further the candidate's understanding of Parkinson's disease pathophysiology and her training in experimental skills, such as in vivo animal work, epigenetic methods and the use of viral vectors for gene delivery. She will continue her subspecialty training and clinical practice in the diagnosis and treatment of Parkinson's disease and related disorders. In addition, the candidate will pursue formal studies in clinical research training to acquire knowledge on the major issues for converting a molecule neuroprotective in animal models into treatment for human patients. By the end of the five-year plan, the candidate expects to be fully equipped to direct research on Parkinson's disease mechanisms and the translation of such research into potential therapies. The 14-3-3 proteins appear promising, but whether or not they turn out to become practical neuroprotective agents, the experience gained in studying these proteins will have taught the candidate how to test whether candidate proteins are truly protective and, if so, how to begin developing them into clinical therapy.